Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-27T14:35:23.612Z Has data issue: false hasContentIssue false
  • English
  • Français

Wave dynamics of an electrojet: generalized Farley–Buneman instability

Published online by Cambridge University Press:  01 October 2007

JAMES F. McKENZIE
JAMES F. McKENZIE*
Affiliation:
Department of Physics, IGPP, University of California, Riverside, CA, 92521USA School of Pure and Applied Physics and the Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, University of KwaZulu-Natal, Durban 4001, South Africa
Get access Rights & Permissions [Opens in a new window]

Abstract

In this paper we generalize the classical Farley–Buneman (FB) instability to include space-charge effects and finite electron inertia. The former effect makes the ion-acoustic wave dispersive with the usual resonance appearing at the ion plasma frequency, but other than that the structure of the FB instability remains intact. However, the inclusion of the latter, finite electron inertia, gives rise to the propagating electron-cyclotron mode, albeit modified by collisions. In the presence of differential electron streaming relative to the ions, the interaction between this mode, attempting to propagate against the stream, but convected forward by the stream, and a forward propagating ion-acoustic mode, gives rise to a new instability distinct from the FB instability. The process may be thought of in terms of the coupling between negative energy waves (electron-cyclotron waves attempting to propagate against the stream) and positive energy waves (forward propagating ion-acoustic waves). In principle, the instability simply requires super-ion acoustic streaming electrons and the corresponding growth rates are of the order of one half of the lower hybrid frequency, which are faster than the corresponding FB growth rates. For conditions appropriate to the middle day-side E-region this instability excites a narrow band of frequencies just below the ion plasma frequency. Its role in the generation of electrojet irregularities may be as important as the classical FB instability.

Type
Papers
Information
Journal of Plasma Physics , Volume 73 , Issue 5 , October 2007 , pp. 701 - 713
Copyright
Copyright © Cambridge University Press 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Buchert, S. C., Hagfors, T. and McKenzie, J. F. 2006 Effects of electrojet irregularities on DC current flow. J. Geophys. Res. 111, A02305, doi:10.1029/2004/JA010788.Google Scholar
Cairns, R. A. 1979 The role of negative energy waves in some instabilities of parallel flows. Fluid Mech. 92, 1–14.CrossRefGoogle Scholar
Fejer, B. G., Providaki, J. and Farley, D. T. 1984 Theory of plasma waves in Auroral E-region. J. Geophys. Res. 89 (A9), 7487–7494.CrossRefGoogle Scholar
Hamza, A. M. and St.-Maurice, J.-P. 1993 A turbulent theoretical framework for the study of current-driven E region irregularities at high altitudes: basic derivation and application to gradient-free situations. J. Geophys. Res. 12, 40–43.Google Scholar
Huba, J. D. 1994 NRL Plasma Formulary. NRL/PU/6790-94-265, Naval Research Laboratory, Washington, DC, p. 42.Google Scholar
Janhunen, P. 1995 On recent developments in E-region irregularity simulations and a summary of related theory. Ann. Geophys. 13, 791–806.Google Scholar
Liperovsky, V. A., Meister, C.-V. and Kustov, A. V. 2006 Stabilization of the Farley–Buneman instability by three waves interaction as consequence of the modification of the speed of energy transfer from an electric field. Astron. Nachr. 320 (2), 77–85.3.0.CO;2-T>CrossRefGoogle Scholar
McKenzie, J. F. and Hagfors, T. 1996 Electrostatic parametric resonances in a plasma, revisited. J. Plasma Phys. 55 (3), 359–385.CrossRefGoogle Scholar
McKenzie, J. F., Marsch, E., Baumgärtel, K. and Sauer, K. 1993 Wave and stability properties of multi-ion plasmas with applications to winds and flows. Ann. Geophys. 11, 341–353.Google Scholar
Milikh, G. M. and Dimant, Y. S. 2003 Model of anomalous electron heating in the E region: 2 Detailed numerical modeling. J. Geophys. Res. 108 (A9), 1351, doi:10.1029/2002/JA009527.Google Scholar
Oppenheim, M., Otani, N. and Ronchi, C. 1996 Saturation of the Farley–Buneman instability via nonlinear electron E× B drifts. J. Geophys. Res. 101, 17273–17286.CrossRefGoogle Scholar
Robinson, T. R. 1994 The role of E-region plasma turbulence in the enhanced absorption of hf radio waves in the auroral ionosphere: implications for RF heating of the auroral electrojet. Ann. Geophys. 12, 316–332.CrossRefGoogle Scholar
Robinson, T. R. 1998 The effects of small scale field aligned irregularities on E-region conductivities: implications for electron thermal processes. Adv. Space Res. 22, 1357–1360.CrossRefGoogle Scholar
Sudan, R. N. 1983 Nonlinear theory of type I irregularities in the equitorial electrojet. J. Geophys. Res. 88, 40.Google Scholar
Weinstock, J. and Sleeper, A. 1972 Nonlinear saturation of type I irregularities in the equitorial electrojet. J. Geophys. Res. 77, 3621–3629.CrossRefGoogle Scholar